In spot illumination applications, such as scene setting or other atmosphere creating lighting, white light sources with colored filters have been used to a great extent. Lately, as an alternative, illumination systems with colored light sources, such as light emitting diodes, LEDs, have been developed. In systems with colored light sources, the color can be changed by electronic control, and all accessible colors are always available.
In spot illumination applications, the homogeneity of the emitted light is of great importance, regardless of whether the spot illumination system is color controllable or not.
One example of an illumination system for spot illumination is described in U.S. Pat. No. 6,200,002, wherein a tubular collimator collimates light from a light source array arranged in the collimator entrance. Although U.S. Pat. No. 6,200,002 provides for an improved homogeneity compared to previous illumination systems, further improved homogeneity of the emitted light would be desirable.